In recent years, portable playback appliances, to which content such as AV (audiovidual) content is loaded to be viewed outside home, have come into widespread use.
There may be a case where AV content has a limited period of time during which can be viewed. In order to manage such AV content, usage expiration information and the AV content can be managed together. For example, Patent Literature 1 discloses what is shown in FIG. 1. When a date-and-time change operation is executed, date-and-time change information is stored. Then, when music content is to be played back, it is determined whether or not the date-and-time change information is present. When the date-and-time change information is determined to be stored, playback of the music content is limited. Thus, in the case where the date-and-time change operation has been executed, the music content cannot be played back.